The present disclosure relates to a ceramic catalyst, a method of manufacturing a ceramic catalyst, and a fuel cell, and more particularly, to a ceramic catalyst capable of increasing a catalyst active area, a method of manufacturing a ceramic catalyst, and a fuel cell.
A fuel cell is a power generation device that utilizes a technique in which the chemical energy of fuel is directly converted into an electric energy by an electrochemical reaction, and is an electrochemical power generation device that supplies hydrogen and oxygen in the air to a positive electrode and a negative electrode, respectively, to continuously produce electricity.
Recently, biomethane, which is a main component of natural gas, and has an advantage of being capable of substituting energy sources having limited reserves such as petroleum and coal, is highlighted as the fuel for fuel cells. Biomethane is produced by removing unnecessary substances from biogas composed of methane and carbon dioxide formed by decomposition of organic matter and performing purification such that the concentration of methane becomes about 98%.
In order to operate the fuel cell using such biomethane as fuel, it is necessary to decompose methane to produce hydrogen. Technical methods for producing hydrogen are largely classified into: firstly, a method based on a hydrocarbon material, for example, a methane steam reforming method, a partial oxidation method of heavy oil, and a catalyst decomposition of natural gas; secondly, a method using thermochemistry; and thirdly, a combination method of the two methods.
In the fuel cell, hydrogen is produced by decomposing methane through a high-temperature pyrolysis method, which decomposes directly substances mainly only by heat, to produce hydrogen, and reaction is carried out at high temperature under low pressure in order to increase a methane decomposition rate. However, when the reaction is carried out at high temperature so as to obtain a high decomposition rate, a polymer electrolyte membrane in a polymer electrolyte fuel cell is melted to lose the function as an ion conductor, and the fuel cell is thus unable to be operated. In this case, it is possible to lower the reaction temperature by using a metal catalyst such as copper, gold or the like which is widely used, but the activity of the catalyst may be deteriorated due to byproducts such as carbon and carbon monoxide generated during a decomposition reaction, thereby acting as a fatal factor to the catalyst.
Further, in order to cause the catalyst reaction to occur well, it is necessary to have a large catalyst active area per unit area so that a reactant may contact the catalyst in a wider area. However, the catalyst generally used has a spherical shape, and when the catalyst is used in the fuel cell, spherical catalyst particles are used to be dispersed and supported in the limited space of a catalyst support, so that the catalyst activity may become low due to a small specific surface area per unit area.